1. Field
The present disclosure generally relates to methods and apparatus for performing channel tree operations in a communication system, and more particularly to ordering a channel tree to effect improved computation speed for channel tree operations for scheduling channel resources in the communication system.
2. Background
In communication systems, such as Orthogonal Frequency Division Multiplexed Access (OFDMA) systems, bandwidth of available resources may be represented as a hierarchical graph or “tree” of nodes (termed a “channel tree”) representing system channels, which may be one or more frequencies, subcarriers, or tones. In future OFDMA systems, such as Ultra-Mobile Broadband (UMB), representation of available bandwidth as a channel tree utilizes certain well defined relationships between the nodes. As is known, a channel tree is used to assign frequencies to users in a communication network to ensure diversity among a plurality of receivers in the communication network. Various channel tree concepts are discussed in U.S. patent application Ser. No. 11/209,246 entitled “FREQUENCY HOPPING DESIGN FOR SINGLE CARRIER FDMA SYSTEMS” filed Aug. 22, 2005, and incorporated herein in its entirety.
Channel trees are typically used to signal Access Terminal (AT) assignments and overall bandwidth management by a scheduler unit. Because the scheduler is one of the more time sensitive pieces of an OFDMA system as an example, it may be appreciated that it is beneficial to have a fast and efficient performance of channel tree operations. Channel trees, however, conventionally are implemented using linked lists. In particular, this type of implementation involves a tree structure in which nodes are linked via pointers. The linked list structure, however, requires scanning of the structure for the majority of operations performed, thus limiting the speed and efficiency of the performance of channel tree operations.